1. Field of the Invention
The present invention relates to a ceramics dispersion liquid, a hydrophilic coating agent using the same, and a photocatalytic functional product. The ceramics dispersion liquid may be used for various materials to have hydrophilic properties.
2. Related Art of the Invention
Various ceramics dispersion liquids have been reported. In recent years, it is noticed that a ceramics dispersion liquid may make a surface of various materials hydrophilic by a photocatalytic process. Here, “to make a surface hydrophilic by a photocatalytic process” means to activate, by light irradiation, a catalyst in a film which is made from a dispersion liquid and is applied on a material surface, thereby hydrophilizing the applied film itself; to decompose low hydrophilic materials (i.e., lipophilic materials and the like) on an applied-film surface, thereby recovering hydrophilic properties of the applied film; or both of them. For example, Laid-Open Publication W096/29375 discloses that a titanium oxide photocatalyst coating agent which is obtained by mixing titania sol with silica sol may provide such an applied film. The titanium oxide photocatalyst coating agent for forming a hydrophilic film is also sold at a market. With light irradiation using a special light source such as germicidal lamp, applied films made from such known titanium oxide photocatalyst coating agents may have a certain degree of hydrophilic properties to provide an anti-clouding effect and a self-cleaning effect at some degrees. However, the applied films have problems such that, once contamination of lipophilic materials spreads to all over the applied film, long period of time would be needed to recover the hydrophilic properties. Accordingly, further improvement has been demanded.